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研究了高密度脉冲电流对过共晶Al 19Si合金凝固组织的影响。结果表明 :未经任何处理的试样凝固组织中含有大量的长杆状初生Si,其长宽比较大 ,且共晶Si尺寸较大 ;而经过高密度脉冲电流处理后 ,凝固组织中初生Si转变为块状 ,长宽比显著减小 ,共晶Si呈短杆状 ,尺寸较小 ,另外在试样的局部存在初生Si晶粒破碎现象 ,这是高密度脉冲电流在熔体内部产生不平衡的电磁力而导致不平衡剪切的结果
The effect of high density pulse current on the solidification microstructure of hypereutectic Al 19 Si alloy was studied. The results show that there is a large amount of long rod-like primary Si in the solidified microstructure without any treatment, which has a large aspect ratio and a large eutectic Si size. After high density pulse current treatment, the primary Si Into a massive, significantly reduced aspect ratio, eutectic Si was short rod-shaped, smaller size, in addition to the local existence of primary Si grain crushing phenomenon, which is a high-density pulse current generated inside the melt is not Balanced electromagnetic force results in unbalanced shear